Congratulations on your new baby boy in spanish

¡Felicitaciones por el nacimiento de su bebé varón!

(Translation: Congratulations on the birth of your baby boy!)

Other ways to express congratulations on a new baby boy in Spanish:

Note: In Spanish-speaking countries, it's common to use the formal form of address (e.g. "usted" instead of "tú") when expressing congratulations or well-wishes, especially when speaking to someone you don't know well or who is older than you.